Boonton 4530 Peak Power Meter User Manual - Manual (Page 128)

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Chapter 4 Boonton Electronics
Remote Operation 4530 Series RF Power Meter
*OPC
Description: Clear or read the OPC (OPeration Complete) status flag. Issuing this command with no
arguments clears the flag (resets it to zero), and the query form of the command returns the
flag’s current value. The flag is bit 0 (the LSB) of the Standard Event Status Register (ESR),
and is set to one when all pending operations have completed. Using the OPC flag requires
that it be immediately cleared before an operation is started. Once the flag has been cleared
by sending *OPC, the next command should be issued. After this, the flag may be queried
by *OPC? until a value of one is returned, indicating the command has completed. Note
that the query is not a true query - a value of zero will never be returned. Rather, *OPC? will
not return a result until the OPC flag has been set to one by the completion of the previous
operation. This has the disadvantage that the GPIB will be “hung” while waiting for OPC to
become true. Another way to handle this is to enable the OPC bit (bit 0) in the Standard
Event Status Enable mask so an SRQ is generated when the operation completes.
Syntax: *OPC[?]
Returns: Query form returns 1, when pending operation is complete
Valid Modes: Any
*RST
Description: Perform a global reset of the instrument, which sets most registers and measurement param-
eters to default values.
Syntax: *RST
Argument: None
Valid Modes: Any
*SRE
Description: Set or return the mask value in the Service Request Enable Register. This value is used to
enable particular bits for generating a service request (SRQ) over the GPIB when certain
conditions exist in the STatus Byte register. When a mask bit in the SRE Register is set, and
the corresponding STB register bit goes true, an SRQ will be generated. No SRQ can be
generated for that condition if the mask bit is clear. The bits in the Status Byte register are
generally summary bits, which are the logical OR of the enabled bits from other registers.
See the
*STB command for bit assignments.
Syntax: *SRE <n>
Argument: <n> = 0 to 255
Valid Modes: Any